Thickness on on side of the printed model

Hey there,…

I’m having an issue with the vertex 8400.

So let me say I’m printing a sort of coin it is 5mm thick.
Eveything starts fine but soon , the piece where the coin is open starts to get thicker. Then the printhed always runs in the thicker part and it hets worser each layer. When the coint is done, the keyhole is completely messed up and the coin is not really round.


I already turned the coin 90° in de model so it has printed with the keyhole 'at the north side and also on the east-side"
I did that to figure out it is not the problem with the printbedheight.

Somebody knows how this problem can be solved or what I’m doing wrong?

Kind regards.

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